OTTAWA—A growing number of Canadian exporters were saying the NAFTA talks were having a negative impact on their operations even before the trade dispute with the United States escalated in recent weeks.

A survey done for Export Development Canada found 28 per cent of the 1,000 exporters asked said the NAFTA talks had a negative impact on their Canadian operations.

However, the bi-annual survey found overall trade confidence increased to 76.5 per cent from 73.5 per cent in the previous questionnaire.

The survey was done from April 18 to May 11, before the United States ended an exemption for Canada on the global steel and aluminum tariffs it had put in place in March.